The data communicated between two end users may pass through several layers of protocols for assuring proper flow of data through the system. A packet of data may be transmitted over several time slots. Each time slot is transmitted over the air, for example, from a base station to a mobile station on a downlink or from a mobile station to a base station on an uplink. The transmission on the uplink may be in accordance with a selected transmission time interval (TTI) parameter. For example, TTI parameter may have four possible values, 0, 1, 2 and 3. If TTI parameter is set to 0 for example, the transmission interval may be for one time frame on the uplink from a mobile station. Similarly, the transmission interval for TTI values 1, 2 and 3 may be respectively for 2, 4 and 8 time frames. One time frame may have fifteen time slots, and may be for a limited and defined duration. The data generated for transmission over the air may be multiplexed into multiple transport channels. Each transport channel has a set of blocks of data, where the blocks may have the same size. Since the amount of data for transmission may vary for each transmission, the set of data blocks may be for different number of blocks and different size at different times.
The transmissions over the air on the uplink may be in accordance with a variety of parameters defining a transport format combination in a code division multiple access communication system. A transport format identifies a number of data blocks in a set of data blocks and the size of the data blocks in the set of data blocks. A transport format is selected such that the receiving station is able to decode the data with minimal error or at an acceptable error level. The selection of a transport format depends on the data rate, the amount of data in each slot time and the transmission power level. As a result, there may be a large number of transport format combinations that the system may need to support. When the transmitter receives the data for transmission over the air on the uplink, the transmitter eliminates a number of transport formats that may not be used for transmission of the received set of data blocks. The process of eliminating the unacceptable transport formats may be performed before every transmission time interval. Therefore, in an example, if TTI parameter is set to 0, the process for determining and eliminating unacceptable transport formats may have to be repeated every time frame on the uplink. The process of eliminating the unacceptable transport formats may take a substantial processing power and time.
Therefore, there is a need for an efficient method, apparatus and system for determining the unacceptable transport formats for transmission of data in a communication system.